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What's the @ in front of a string in C#?
...string verbatim = @"foo\bar";
string regular = "foo\\bar";
Here verbatim and regular have the same contents.
It also allows multi-line contents - which can be very handy for SQL:
string select = @"
SELECT Foo
FROM Bar
WHERE Name='Baz'";
The one bit of escaping which is necessary for verbatim s...
How to import multiple .csv files at once?
...you have those CSVs in a single directory--your current working directory--and that all of them have the lower-case extension .csv.
If you then want to combine those data frames into a single data frame, see the solutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or ...
How to remove a key from a Python dictionary?
...y', None)
This will return my_dict[key] if key exists in the dictionary, and None otherwise. If the second parameter is not specified (ie. my_dict.pop('key')) and key does not exist, a KeyError is raised.
To delete a key that is guaranteed to exist, you can also use
del my_dict['key']
This wil...
CSS does the width include the padding?
...
IE used to use the more-convenient-but-non-standard "border-box" box model. In this model, the width of an element includes the padding and borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing brow...
java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused
...the emulator.
If you are referring your localhost on your system from the Android emulator then you have to use http://10.0.2.2:8080/ Because Android emulator runs in a Virtual Machine therefore here 127.0.0.1 or localhost will be emulator's own loopback address.
Refer: Emulator Networking
...
Dynamic variable names in Bash
...
Use an associative array, with command names as keys.
# Requires bash 4, though
declare -A magic_variable=()
function grep_search() {
magic_variable[$1]=$( ls | tail -1 )
echo ${magic_variable[$1]}
}
If you can't use associative arrays (e.g., you m...
git add, commit and push commands in one?
Is there any way to use these three commands in one?
32 Answers
32
...
How many String objects will be created when using a plus sign?
...;
Furthermore, the compiler will remove extraneous constant expressions, and only emit them if they are used or exposed. For instance, this program:
const String one = "1";
const String two = "1";
const String result = one + two + "34";
public static void main(string[] args) {
Console.Out.W...
“open/close” SqlConnection or keep open?
...d Dec 14 '10 at 13:02
Adriaan StanderAdriaan Stander
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What is “above-the-fold content” in Google Pagespeed?
...on't need to scroll to see. Obviously, this varies depending on the device and its orientation, so you may need to generalize and maybe find some workable common options, maybe one targeting smartphones, one for tablets, and one for larger desktops.
As for what CSS they are talking about, they are ...